#include <unistd.h>
#include <stdio.h>

int main(int argc,char* argv[])
{
  //execl("/bin/ls","ls","-l",NULL);

  //execlp("ls","ls","-l",NULL);
 // char* env_mod[] = {"aa","bb"};
 // execle("/bin/ls","ls","-l",NULL,env_mod);
  
  /*char* buf[] = {
    "ls",
    "-l",
    NULL
  };
  execv("/bin/ls",buf);
  */

  char* buf[] = {
    "ls",
    "-l",
    NULL

  };
  execvp("ls", buf);
  return 0;
}
